Facial Skin Care Instruction by Medical Professionals Using Microneedle Cream: The 8‐Week Prospective, Randomized, Single‐Blinded for Examiners Trial in Asians

BACKGROUND: Skin care is widely regarded as a fundamental component of self-care. However, few studies have systematically evaluated the effects of structured skin care instruction on both objective parameters and subjective perceptions. This study aims to elucidate these effects through a controlled clinical investigation. METHODS: This clinical trial was conducted at the University of Tokyo Hospital between July and September 2023. Twenty-one healthy women aged 30-60 years applied a microneedle cream to the face for 8 weeks. They were randomly assigned to either the intervention group, which received skin care instructions from the start, or the control group, which received them after 4 weeks. Skin hydration, transepidermal water loss, viscoelasticity, and melanin content were assessed at baseline, week 4, and week 8. Subjective evaluations were obtained via structured questionnaires. Statistical analyses were conducted using Prism (version 10.2.3). RESULTS: At week 4, the intervention group showed significantly greater improvements in skin hydration (intracorneal water content: -0.98% ± 13.49% [control] vs. 14.06% ± 14.61% [intervention], p < 0.05) and elasticity (R7: -3.48% ± 10.36% [control] vs. 7.92% ± 10.29% [intervention], p < 0.05) compared to the control group. At week 8, melanin pigmentation was significantly reduced in the intervention group (Mark-Vu: 11.44% ± 26.67% [control] vs. -15.01% ± 11.10% [intervention], p < 0.05). Subjective assessments were consistent with these objective results, reflecting improved skin perception. CONCLUSIONS: This is the first study to demonstrate that appropriate skin care practices can lead to the moisturizing, firming, and elasticity effects of a microneedle cream. These findings highlight the importance of proper product use in maximizing the efficacy of skin care interventions. TRIAL REGISTRATION: UMIN: UMIN000052080.